> Someone help me out here. I am tired after a long day and may have
> some typos. There is both capacitive and inductive coupling to the
> loop in the slug in the Bird watt meter.
You are not the one who needs help.
<snip>
> And think about it. You get the same reflected power for the
> same
> incident power if the load resistor is 100 ohms or 25 ohms.
> Either produces a 2:1 SWR but a 100 ohm resistor would produce 1/4 the
> current as a 25 ohm resistor. OHM's law still applies.
> The meter does not precisely measure power for all load
> conditions
> but it is real close when the load resistance is close to 50 ohms.
Except for that very last sentence Bill.
The meter works VERY well for measuring power as long as you
subtract the reflected power from the forward power, as my
measurement examples have clearly shown. Theory says it should,
and it actually does.
With a 150 ohm load, my Bird 43 read (within resolution and
tolerances of the meter) EXACTLY the same power deliver to the
load as it did with a 50 ohm load. All I need to do was subtract
reverse from forward power, just like the Bird manual says.
It is very easy to prove.
73, Tom W8JI
W8JI@contesting.com
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